1. Field of the Invention
This invention relates to a surgical system and method for the repair of severed peripheral nerves, and in particular, to a surgical system for cavernous nerve grafting and method of cavernous nerve grafting.
2. Description of Related Art
Injury to a nerve can result in a partial or total loss of the sensation, control, or use of a member or portion of the body. Neurorrhaphy is a surgical procedure for the repair of lacerated or severed peripheral nerves by suturing the ends of a severed nerve together. The use of neurorrhaphy has enhanced the surgeon""s ability to reattach amputated body parts, to achieve composite tissue transfer, and to graft nerves. Although neurorrhaphy methods currently exist, such methods are not always possible and are commonly not completely successful in achieving a restoration of sensation, control, and use of the affected portion of the body.
A repair is satisfactory when it is executed with as little trauma as possible and when alignment of the severed nerve ends is achieved. It is difficult to fulfill the requirements without magnification, micro-surgical instruments, and the finest of sutures. Despite the advances that have been made to date, the re-establishment of normal function in the damaged nerve is difficult to achieve.
The success of such procedures is still limited because the current methods of suturing severed nerves is difficult, time-consuming, and often yields poor functional results due to a variety of factors. The most critical factor of technique in neurorrhaphy is the accurate approximation of the cut ends of the fasciculi (nerve bundles within the nerve trunk). Even though other factors may be ideal, the neurorrhaphy will fail if a significant number of fasciculi are not sufficiently aligned. This is because motor axons regenerating through the sheaths of sensory nerves, and vice versa, will give no return of sensory or motor function.
Alignment of the fasciculi may be achieved by visually orienting the fasciculi of the severed ends of the nerve. Alternatively, the fasciculi may be aligned by visually orienting the blood vessels disposed along the length of the severed ends of the nerve. In either approach, an unobstructed view of the severed nerve ends is necessary.
Another factor is the tendency of severed nerve ends to contract and pull apart after suffering damage. Consequently, when connection of the severed nerve ends is attempted, atensile force may be created in the severed ends as they are drawn together, complicating both the process of rejoining the severed ends, and the healing process. For example, during the healing process it is difficult to alleviate the tensile force located at the severed nerve ends. This tensile force may cause the nerve ends to pull loose from the connection, thereby resulting in decreased functional connection of the nerve or nerve graft.
Other techniques involve using a sheath, or cylindrically shaped tube, to encase the nerve in an attempt to maintain the severed nerve ends in proper alignment to facilitate healing, and thus, functional connection of the severed nerve ends. These techniques limit the surgeon""s vision thereby hampering the surgeon""s ability to align the severed nerve ends. The absence of a cylindrically shaped tube or sheath disposed over the severed nerve, as in the present invention, permits continuous visibility of the anastomotic site during alignment of the severed nerve ends.
Accordingly, prior to the development of the present invention, there has been no surgical system for repairing severed nerves, method of repairing severed nerves, or method of adjoining severed nerves, which: increases the visibility of the anastomotic site thereby facilitating proper alignment of the severed nerve ends; and decreases trauma to the severed nerve ends thereby facilitating healing of the severed nerve. Therefore, the art has sought a surgical system for repairing severed nerves, method of repairing severed nerves, and method of adjoining severed nerves, which: increases the visibility of the anastomotic site thereby facilitating proper alignment of the severed nerve ends; and decreases trauma to the severed nerve ends thereby facilitating healing of the severed nerve. It is believed that the present invention will achieve these objectives and overcome the disadvantages of other surgical systems, methods of repairing severed nerves, and methods of adjoining severed nerves in the field of the invention, but its results or effects are still dependent upon the skill and training of the operators and surgeons.
In accordance with the invention the foregoing advantages have been achieved through the present surgical system for repairing severed nerves comprising: at least one suture having a first end and a second end; at least one clip having a support member and at least one arm having a length; and at least one retaining member having a first end and a second end.
A further feature of the surgical system for repairing severed nerves is that the first end of the suture may include a needle. Another feature of the surgical system for repairing severed nerves is that the second end of the suture may include an expanded tail. An additional feature of the surgical system for repairing severed nerves is that the clip may include two arms. Still another feature of the surgical system for repairing severed nerves is that the clip may be formed out of metal. A further feature of the surgical system for repairing severed nerves is that the clip may be formed out of plastic. Another feature of the surgical system for repairing severed nerves is that the clip may be formed out of an absorbable polymer or copolymer. An additional feature of the surgical system for repairing severed nerves is that the retaining member may be formed out of plastic. Still another feature of the surgical system for repairing severed nerves is that the retaining member may be formed out of an absorbable polymer or copolymer. A further feature of the surgical system for repairing severed nerves is that each of the two arms may include equal lengths. Another feature of the surgical system for repairing severed nerves is that each of the two arms may include a length of about 2.5 millimeters. An additional feature of the surgical system for repairing severed nerves is that the support member may include a length of about 1.5 millimeters. Still another feature of the surgical system for repairing severed nerve ends is that the retaining member may include a length of about 3.0 millimeters. A further feature of the surgical system for repairing severed nerves is that the suture may include a length of about 3.0 centimeters.
In accordance with the invention the foregoing advantages have also been achieved through the present method of repairing severed nerves comprising the steps of: providing a severed nerve having a first severed end and a second severed end; forming a suture having a first end and a second end, wherein the first end includes a needle and the second end includes an expanded tail; aligning the first severed end with the second severed end; inserting the needle through the first and second severed ends; securing the expanded tail of the suture to either the first severed end or the second severed end; removing the needle from the first end of the suture; placing the first end of the suture and a retaining member within a clip; and capturing the first end of the suture and the retaining member within the clip.
A further feature of the method of repairing severed nerves is that the first end of the suture and the retaining member may be captured within the clip by deforming the clip. Another feature of the method of repairing severed nerves is that the first end of the suture may be inserted through the retaining member. An additional feature of the method of repairing severed nerves is that the expanded tail may be formed by heating the second end of the suture and shaping the second end into the expanded tail.
In accordance with the invention the foregoing advantages have also been achieved through the present method of adjoining severed nerve ends comprising the steps of: providing a first severed nerve end and a second severed nerve end; aligning first severed nerve end and second severed nerve end; inserting through first severed nerve end and second severed nerve end a suture, wherein the suture includes an expanded tail; securing the expanded tail of the suture to either the first severed nerve end or the second severed nerve end; placing a retaining member and the suture within a clip; and capturing the retaining member and the suture within the clip thereby adjoining first severed nerve end and second severed nerve end.
A further feature of the method of adjoining severed nerve ends is that the first or second severed nerve end may be located on a nerve graft.
The surgical systems for repairing severed nerves, methods of repairing severed nerves, and methods of adjoining severed nerves of the present invention have the advantages of: increasing the visibility of the anastomotic site thereby facilitating proper alignment of the severed nerve ends; and decreasing trauma to the severed nerve ends thereby facilitating healing of the severed nerve. As mentioned above, it is believed that the present invention will achieve these objectives and overcome the disadvantages of other surgical systems and methods in the field of the invention, but its results or effects are still dependent upon the skill and training of the operators and surgeons.